Granulocytapheresis in the treatment of patients with rheumatoid arthritis.

The G-1 column is an extracorporeal type granulocytapheresis device packed with 220 g cellulose acetate beads to which granulocytes and monocytes specifically adhere. A total of 59 rheumatoid arthritis patients with elevated granulocyte counts from 4 hospitals in Japan received 2 apheresis sessions of 1 h duration/week for a total of 8 times over a period of 4 weeks. About 55% of the leukocytes which entered the G-1 column were adsorbed onto the beads: 95% were granulocytes, 3.5% monocytes, and 0.4% lymphocytes. Clinical and efficacy assessments showed improvements in swollen joints (p < 0.01), tender joints (p < 0.001), the active joint score (p < 0.001), duration of morning stiffness (p < 0.01), and grip strength (p < 0.001). In good responders, the improvements were observed for up to 12 weeks following the last apheresis. Exacerbation was noted in 2 patients. It is suggested that the efficacy of the G-1 column is attributable to the removal or suppression of hyperactive leukocytes and inflammatory cytokines, inducing a kind of immunomodulation.